Concrete-pipe machine



J. G. ZWICKER.

CONCRETE PIPE MACHINE. APPLICATION FILED APR. 12, I926.

1,418,859; v PatentedJune 6, 1922.

5 suits- 53551 l. 67 68 WITNESS INVENTQR %a;, zmzq BY A TTOR NE YS I. G. ZWICKE R. CONCRETE PIPE MACHINE. APPLICATION man APR. 1.2. 19.20.

1,418,859. PatenteaJune e, 1922.

' 5 SHEETS-SHEET 2.

A TTORNEYS J. G. ZWlCKER. CONCRETE PIPE MACHI'NE. APPLICATION FILED APR. 12. 1920.

Pmtea June 6,1922.

5 SHEETS SHEET 4.

IN V EN TOR A TTORNE YS WITNESS J. G. ZWICKER. CONCRETE PIPE MACHINE. APPLICATION FILED APR. 12, 1920.

Patented June 6, 1922.

5 SHEETS-SHEET 5 INVENTOR By ge; 5. Zm

WITNESS A TTOR NE YS earner series.

JULIUS G. ZWIGKER, OF BERKELEY, CALIFORNIA.

CONCRETE-PIPE MACHINE.

reassess.

Application filed April 12,

.To all whoa/t it may concern:

Be it known that I, JULIUs 5i. Zwionnn, a citizen of the United States, residing at Berkeley, in the county of Alameda and State of California, have invented certain new and useful Improvements in Concrete-Pipe Machines, of which the following is a specification.

My invention relates to an apparatus for molding pipe sections, and is particularly adapted for the use of concrete as the molded material, and for the production of such sections with inter-fitting threaded ends, in this respect being similar in purpose to the concrete-pipe machine for which Jnited States Letters Patent No. 1275353 was issued to me on August 13, 1918, to which reference may he made if desired.

Broadly, the objects of my present invention are similar to those set forth in the specification of said patent, viz:jto provide a moldin apparatus by means of which a wet or poured concrete mixture may be artificially and rapidly set by the forcible expression of the greater portion of the water contained in the mixture, to enable its immediate removal from the mold; and further to provide, in such an apparatus, a mold of absolute accuracy, so that every article molded therein will be identical with every other article. The advantages gained by the attainment of these objects are fully expounded in the specification of said patent, and are now clearly recognized in the art, so that they need not be entered into here.

As in the machine described in said patent, I now make use. in the present apparatus, of separate ring molds for forming the threads upon the ends of the pipe section. Moreover. in the present apparatus. I compress the pipe section in a manner broadly similar to that employed in said prior machine. namely by pressure applied in a direction at right angles to the longitudinal axis of the molds. that is, to the side of the section to be molded.

More specifically. the objects of my present invention are to provide a machine for the described purposein which the interior surface of the molded pipe section can be given a smooth finish. similar to that ob tained by the well-known process of hand trowelling concrete surfaces, so that: said interior surface. when dry. is smooth. hard, and impervious: and further to provide a machine capable of making concrete pipe Specification of Letters Patent.

Patented June 6, 1922.

1920. Serial No. 373,160.

sections in the least possible time. F or the attainment of this latter object, I employ power means for performing all the major operations of the process, so that said operations are accomplished swiftly and accurately without exertion on the part of the operator. In fact, by continuous operation of the machine hereinafter described, I am able to make one pipe'section every minute.

A still further object of my invention is to provide means for adjustment of the machine so that pipe sections of various diameters and thickness, within certain limits, can be made in one machine, and so that the degree of compression can be properly correlated to the amount of concrete in the mold, regardless of the size or thickness of the pipe formed.

Although my invention is herewith described and illustrated as a machine for making concrete pipe sections, it is to be understood that other materials capable of being molded under pressure may be used, and by making minor alterations in the form and construction of the machine, articles other than pipe sections may be formed.

lVith this in view, my invention will now be described in detail with reference to the accompanying sheets of drawings, where- 1n: 7

Fig. 1 is a side elevation of my complete machine.

Fig. 2 is a vertical section, enlarged, of the upper portion of the machine, showing the molds and associated mechanism.

Fig. 3 is a horizontal section in two planes, taken approximately on the lines a0 and -72 of Fig. 2 and viewed in the direction of the arrows.

Fig. 4.;is a vertical, sectional detail, enlarged, showing portions of the upper ends of the molds, the upper thread mold, and associated mechanism.

5 is a vertical sectional detail, enlarged, of the feed hopper.

Fig. 6 is a central vertical section, enlarged. of the lifting mechanism located in the base of the machine.

Fig. 7 is a top plan view. greatly enlarged. of one each of theinner and outer cylindrical mold segments.

In the drawings. the reference numeral 1 designates the upright columns of a supporting frame. There are preferably four such columns, springing from a base 2, 1, set upon a suitable floor or foundation, the

level of which is represented by the line The upper portions of said columns 1 supports two spaced horizontal circular channels or guides 4, Figs. 1, 2 and 3. Vertical spacer members 5 between said guides 1, serve to hold the same in proper mutual relation.

The circular channels 4, each of which is formed of an upper and a lower plate secured together as by bolts 6, Figs. 2 and 3, have a series of radially disposed inwardly directed guide-ways 7, Figs. 2, 3 and 5, preferably square in cross-section. Within said guide-ways are slidable plungers 8, each of which carries, at its outer end, a roller 9, positioned to bear against the flat surface of a cam block 10, Figs. 2 and 3. Each of said blocks 10 is secured to the inner periphery of a corresponding ring 11 mounted for oscillatory motion in its corresponding circular guide 4;, so that, by the oscillation of said rings 11 the plungers 8 are moved in, or are allowed to be moved out by springs 12, Fig. 3, inserted between shoulders 13 on said plungers and the inner faces of the channels 1-.

On the inner ends of the plungers 8 are formed dowels 14, Fig. 2, which it snugly into sockets in vertically disposed bars 15, Figs. 2 and 8. Each of said bars 15 is thus carried by a pair of vertically aligned plungers 8, one in the upper series and one in the lower. and the entire set of said bars, 1

which are positioned close together, forms a cylindrical vertically disposed cage constituting the outer mold for a section of pipe.

The inner surfaces of the vertical bars or mold segments are formed into a grid by a series of parallel vertically disposed segmental ribs or tongues 16, l ig. 7, whose inner faces are formed upon the arc of a circle, and which are separated, at said inner faces, by very narrow slits 17 leading into enlarged vertical passages 18 between the segmental tongues. The entire surface of the cylinder formed by the bars 15, therefore. comprises a series of closely spaced parallel segments separated by very narrow slits. As the bars 15 are moved in or out by their respective plungel's 8 and springs 12, the diameter of the cylinder formed by said bars is, ol course. decreased or increased, and the spaces between adjacent bars are su'fiicient to permit such contraction and expansion, but in practice, in a machine where the diameter of the cylinder is about eight inches. and which. is built up of sixteen bars, as in the machine herewith illustrated, the maximum distance between adjacent bars 15 need not be greater than three sixty-fourths of an inch; and in a machine of this size I prefer to make the slits 17 between adjacent segments 16b t the grid about one siXty fourth of an inch.

Rotation of the cam rings 11, to cause contraction or expansion of the cylindrical mold, is effected by means of a pair of oppositely positioned hydraulic cylinders 19, Fig. 1, set in pivotal supports 20 for horizontal swinging movement. Each of said cylinders 19 has within it a piston 21, Fig. 3, from which extends a piston rod 22, pass ing through a suitable packing gland 23 and a, guide 2-1, and pivotally connected at its outer end with a lever tulcrumed, at 26, at its middle. The outer end of each lever 25 is connected by a. link 27 with a vertical rod 28, Figs. 1. and 3, extending between and connecting the upper and lower rings 11.

Adjustable stops 29 are provided on each piston rod 22 to limit its motion by contacting with the guide 24, and a lineal adjustment 29 is provided for varying the efl'ective length of the piston rod 22.

l'lising from the upper circular guide -"lis a yoke frame 30, Figs. 1 and 2. which has a cross member 31 in which formed a central hub 32, in axial alignment with the center of the cylindrical mold described above. To the lower end of said hub is secured a plate or head Figs. 5, and whose outer edge rests upon a cylindrical cap 34, Figs. 1, 2 and 4. The lower end of said cap is flanged, and rests upon a separate conical flange 35, which, in turn, rests upon and is secured to the upper circular guide 41-, the members 33, 34.- and 35 thus forming an end closure or cap for the cylindrical mold.

The hub 32 supports and provides a hearing for a rotatable tube 36, F 2 and which extends centrally through the outer mold. In the upper end of said tube is fixed a bevel gear 37. I1. and 2. which meshes with a corresponding bevel gear 238 fixed upon the inner end of a horizontal shaft 39 carried in a suitable journal it) and having a pulley 41 fixed upon its outer end. by means of which it and the tube 36 may be rotated.

W'ithin the tube 36 is an axially slidable rod 42. Figs. 1 and 2, which projects through the gear 37 at its upper end and is 'Formed with an annular groove 43, in. which rides the forked end of a lever 4-1. tulcrumet at 415, by means of which said rod 42 may be moved vertically. Said rod 42 carries a series oi tJ1lSV(51'S6l V disposed pins 4-6. Fig.

2. which extend, through vertically directed slots 47 in the tube 36, into conical wedge blocks 18, Figs. 2 and 3, surrounding said tube and slidably mounted thereon.

The mold for the inner surface of the pipe section comprises a series of adjacent vertical bars 49. Figs. 2, 3 and 7, forming a cylinder positioned concentrically within the outer mold. Said bars 49 rest upon a bottom end plate 50, Fig. 2, and a similar end plate 51 is provided at the top, both end plates being carried by the tube 36. Guide members 52 are also carried by the tube 36 immediately within the end plates and 51, said guide members being formed with radial slots or guide ways 53, Fig. 4:, adapted to receive lugs 55% projecting inwardly from the end portions of the bars d9. Springs 55, associated at top and bottom with each of said bars 19, act to draw the same in toward the center.

The bars l9 are formed upon their backs with inwardly projecting lugs 56, Figs. 2 and 3, having inclined faces adapted to. bear against the conical wedge blocks 48, so that by the elevation of the central rod 42, carrying with it the blocks 48, the bars 19 are forced outwardly, and the cylinder forming the inner mold or core is made larger in diameter; and conversely, upon the lowering of the rod 42, said bars are drawn inwardly, by their springs 55, to make said mold smaller.

The outer surfaces of the bars 49 are formed into grids, as in the case of the outer mold bars 15, by a series of vertical segmental ribs 57, Fig. 7, whose outer surfaces are formed upon the arc of a circle, and which are separated, at said outer surfaces, by narrow slits 58 leading into larger vertical passages 58. The spaces between adjacent segmental ribs 57 and between adjacent bars 49 are approximately the same as those in the outer mold construction previously described. The entire inner mold structure or core, being carried by the tube 86, is rotatable by means of power applied to the pulley 41.

Surrounding the upper end portion of the core and lying within the cylindrical shell 34;, is a ring 59, Figs. 2 and ti, suspended by slidable rods 60 from a yoke 61, Figs. 1 and 2, said rods passing through guides 62, Fig. l, in the head plate 33, which is flanged, as shown in Figs. 2 and 4, to permit the ring 59 to be drawn up clear of both the outer and the inner molds. The yoke 61, Fig. is supported by a vertical piston rod 63 which passes through a hydraulic cylinder 6+1: carried by the frame 30, and is connected with a piston 65 within said cylinder. Suitable packing glands 66 are provided where the rod 63 passes through the heads of said cylinder, and the upper end of said rod passes through a gi'iide 67 and is provided with adjustable stops 6S contacting with said guide to limit the motion of said rod.

The ring 59 carries a series of depending spring fingers 69, Figs. 2 and 4, each having on its back a lug 70, Fig. l,adapted to engage a shoulder 71 formed on the inner surface of the cylindrical member 84, so that when the ring 59 is raised from the position shown, the lingers 69 are forced inwardly by the contact of their lugs 70 with said shoulder. The lower ends 7 2, of said fingers 69 are bent inwardly and pointed, to engage and grip the upper thread mold 73.- This thread mold, which is shown in Figs. 1, 2, 4t and 5, is for the purpose of forming the male thread upon the upper end of the pipe section, and as such is provided with an inner flange 74, Fig. a, of such size that it will fit closely about the core when the latter is fully expanded, and an outer flange of the same diameter as the outside of the 7 finished pipe and fittin easily within the- Fig. 1, said truck having wheels 79 adapted to run upon the rails 80 of a suitable track laid between the columns 1 in the lower portion of the machine.

The placing of said lower thread mold upon the truck 78 is the first step in the operation of the machine to make a section of pipe. A reinforcing coil 81, Fig. 1, is then placed, in an upright position. upon said lower thread mold, and the upper thread mold 73 is placed upon the upper end of said coil. The reinforcing coil 81 may be of any suitable construction, but in practice I prefer to use the reinforcing coil for concrete pipes for which United States Letters Patent No. 1267885 was issued to me on May 28, 1918. The truck 78, with the thread molds and the reinforcing coil thereon, is then run into the lower part of the machine, and placed below and in vertical alignment with the inner and outer cylindrical molds described above, as shown in Fig. 1.

ln'this position, the lower thread mold 77 is in vertical alignment above a lifting table 82, Figs. 1 and 6, carried upon the upper end, of a vertically mo uible rod 83, Fig. 6, whose lower end carries a piston 8 1 operatable within a hydraulic cylinder 85. Suitable fluid connections 86 and87 are provided for operating said piston, and a packing gland 88 surrounds the rod 83 where it passes out of the upper end of the cylinder 85. A stop 89 is also provided at the upper end of said cylinder upon which the lifting table 82 seats when in its lowermost position, as shown in Figs. 1 and 6.

The truck 78 having been positioned above the lifting table 82, said table israised, by means of its hydraulic cylinder, and, passing upward through the truck 78 engages and lifts the lower threadmold 77 with the reinforcing coil 81 and the upper thread mold 73 superposed thereon, and positions the some within the annular space between the inner and outer cylindrical molds, as shown in Fig. 2, said inner and outer cylindrical molds having been previously contraeted and expanded, respectively, to the limits of their movement.

The parts now occupy the relative positions shown in Fig. A central dowel 90 on the lifting table 82 has entered a socket ill in the lower end of the central tube 36, thereby centering said lifting table. The inner cylindrical mold is then. expanded, by means of the lever 4:4. to its limit, which correspond:- to the inside dian'ieter of the tinished pipe section. lf lext the ring 59 is raised, by means oi: liuid adniitted to its hydraulic cylinder (i l: below the piston (35, and the spring lingers 39, gripping the upper thread mold 73, cause the same to be litted, along with the ring 59, to the position shown in section in Fig. 5.

On one side of the cylindrical cap member S-la teed hopper 92, Fig. 5, 'WllOSQ lower portion communicates with the annular space between the inner and outer cylindrical molds by means ol an opening 93. A segmental sliding gate 94- is provided for closing said teed opening, and said gate is opera ted by a horizontally disposed hydraulic cylinder 95 having a piston 9b and a piston rod 9? com'iec ed directly with said'gate.

The upper thread mold 723, as shown in Fig. has been raised above said teed opening 9a. The machine is now ready tor pouring. ll et concrete mixture is introduced. through the teed hopper to till the annular space between the inner and outer cylindrical molds, snrrouiuling and embedding within itself the reinforcing coil 81. The gate is then closed by-the action oi? its hydraulic cylinder 95, and the upper thread mold is forced downward, against the wet concrete, by the hydraulic cylinder (Set, Fig. 52, to the limit of its motion, at which point said thread mold is freed from the spring tii'igers (9 by the pass: ge of the lugs below the shoulder '71, Fig. it. The outer cylindrical mold is then contracted, by means of the hydraulic cylinders 19, Figs. 1 and 3, and the associated mechanism described above, to squeeze the water out of the concrete mixture, said water escaping through the slits 17 and 58. Fig. 7, in the outer and inner mold surfaces respectively, and running down through the passages 18 and 58.

in this connection it should be noted that, on account oi? the shape ot the cam surfaces 10, Fig. 3. carried by the oscillatory rings 11, th maximum pressure is exerted upon the outer cylindrical mold at the end of its contracting movement. As the concrete min ture loses its water and becomes more dense, the contracting movement of the outer mold becomes slower and 1ts power increases. The

stops 3'39 and the connections 29 ot the hydraulic cylinders '19 are so adjusted that the pistons 21 come to the end of their travel just as the apices ot the cams ii) are reached, and th length ot travel of said pistons is just suliic ant to cause the proper amount of contraction of the outer mold to dry the amount o l concrete used in the tormation of the pipe section. To make a pipe section having walls o'l greater or less thickness, the outer mold segniients can be replaced by others of ditlerent thickness. and in this case the amount of contraction oi said outer mold must be adjusted, by means oi the stops 29 and the connections 25), to be proportionate to the amount of concrete used. in case it is (relied to make a pipe section oi ditlerent inside diameter, the entire inner cylimlrical mold or core can be replaced with one ol the prijiper size, and this also would necessitate an adjustment of the amount of contraction oi the outer mold.

(icing back to the description ot the operation oi the machine, alter the coi'icrete has been compressed, the inner cylindrical mold or core is contracted by raising the lever H, l igs i and 2, and set to rotating by power applied through the pulley ll. The operator then, by carclul nninipulation of the lm'til' l ll, expands the core gently until its segments justtouch the inner surtace of the pipe section, and by this light rubbing, said, inner surlacc is smoothed. in fact, by skillful uuinipulation oi the hand lever H,

on ctlcct can be produced which closely reseinhles that ol hand-trowelling, so that a smooth inner surface is termed, rich in ceuieut, which when dry, renders the pipe section practically impervious, even at high pressures.

The smoothing operation completed, the core is contracted and stopped; the outer cylindrical mold is enoanded to tree the pipe section; and the l ting table 82, Fig. 2, is let down, to lower the finished pipe section on to the truck 78. Fig. 1.. upon which it is carried out oi? the machine. The thread molds are allowed to remain on the pipe seotion until the concrete has hardened, when they can be easily removed. it is also desirable to leave the pipe section on the truck "2'8 until the m crcte luirdens to avoid possible injury.

lt is necessary to wash the cylindrical molds at trequcnt intervals to prevent the accumulation and setting oi particles of concrete. This need not be done after every cycle of operation, as the particl .s of concrete adhering to the slits and passa ol? the mold segments will not set For several minutes, but in order to accomplish this washing with the least possible delay. I provide the following devices. The cylindrical cap member 34 is formed with an annular chamber 98, Fig. 1, which has awater inlet connection 99 and an annular opening 100 positioned immediately above the drainpassages 18, F '7. of the outer mold sections, so that water, introduced through said inlet connection 99, flows downward through said drain passages 18, washing the same. A similar annular chamber 101, Fig. 4, is formed in thecap member having a water inlet connection 102 and an annular opening 103 through which water can be fed into the drain passages'58, Fig. 7, of the core segments. The surfaces of both inner and outer mold segments are flushed by water introduced through a connection 104;, Fig. 1, into the annular space between the cap member 33 and the cylindrical member 34, and passing on both sides of an annular spreader 101 and the ring 59. All of this flushing water runs out the bottom of the cylindrical molds and is caught in. a basin 105, Fig. 6, formed in the base 2, from which a suitable drain 106 is provided. 7

In order to make possible the shipping or transportation of the machine, without the employment of heavy and costly derricks and other apparatus, I provide means for lowering the entire mechanism upon its supporting columns 1. For this purpose the ring guides 4 are secured to said columns by split ears 107, Figs. 1 and 3, which are normally clamped about said columns by bolts 108. The columns 1 are threaded, as shown in Fig. 1, and upon each is fitted an interiorly threaded nut 109, the 'four nuts 109 being adapted to support the weight of the entire super-structure when the clampbolts 108 are loosened.

The nuts 109 have secured to them sprockets 110, Fig. 3 and these sprockets are inter connected by means of a chain 111. Figs. 1 and 3, so that all four nuts are rotated together. One of the nuts' is provided with ratchet teeth 112 adapted to be engaged by either one of two oppositelyoperating pawls 113 carried by an oscillatorylever 114-.

Therefore, by operating the lever 11 1, the four nuts 109 are rotated. and the entire mechanism can be raised or lowered, depending upon the position of the pawls 113, the ears 107 sliding freely upon the columns 1 after the bolts 108 are loosened. When the super-structure is lowered between the columns 1, the machine can be handled more easily, without fear of damage, and occupies less space in shipment, and, carrying its own lifting mechanism, can be set up quickly and easily without the aid of a derrick.

The mechanism .thus described is also of great assistance in dis-assembling the machine for repair. In this case the upper ring guide 4, Fig. 2, can be clamped upon the columns 1 and the lower one loosened. Then by removing the bolts 6, and lowering the 1. A concrete-pipe machine comprising a rotatable inner mold capable of contraction to free themolded pipe: an outer mold capable of contraction to compress the concrete and of expansion to free the molded pipe: means for contracting and expanding said molds; and means for rotating said inner mold.

2. A concrete-pipe machine comprising a rotatable inner mold capable of contraction and expansion; an outer mold capable of contraction to compress the concrete; means for contracting said outer mold; means for rotating said inner mold; and means for contracting and expanding said inner mold during the rotation thereof.

3. A concrete-pipe machine comprising a rotatable inner mold capable of contraction and expansion; a non-rotatable outer mold; means for rotating said inner mold; and means for contracting and expanding said inner mold during the rotation thereof.

1. A concrete-pipe machine comprising an inner mold; an outer mold capable of contraction to compress the concrete, said outer mold being formed of a plurality of radially movable segments; a cam follower securedto the back of each mold segment; an angularly movable ring'encircling said seg ments; a plurality of cams carried by said ring for engagement with said cam followers, the inclination of said cams decreasing from their bases to their apices, whereby upon partial rotation of said ring, said segments are caused to move inwardly with gradually decreasing speed and increasing force; and means for causing partial'rota tion of said ring.

5. A concrete-pipe machine comprising an inner mold; an outer mold capable of contraction to compress the concrete, said outer mold being formed of a plurality of radially movable segments; a cam follower secured to the back of each mold segment; an angularly movable ring encircling said segments; a plurality of cams carried by said ring for engagement with said cam followers, said cams being formed as chords of the circleof said ring; and means for causing partial rotation of said ring to move said mold segments inwardly. v

6. A concrete-pipe machine comprising an inner mold; an outer mold capable of contraction to compress the concrete, said outer mold being formed of a plurality of radially movable segments; a cam follower secured to the back of each mold segment; an angularly movable ring encircling saidsegments; a plurality of cams carried upon the inner periphery of said ring for engagement wlth said cam followers, each of said cams hay-- ing a flat face formed as'a chord of the circle of said ring; and means for causing partial rotation of said ring to more said mold segments inwardly.

7. A concrete-pipe machine comprising an inner mold; an outer mold capable of contraction to compress the concrete, said outer mold being formed of a plurality of radially movable segments; a cam follower secured to the back of each mold segment; an angularly movable ring encircling said segments; a plurality of cams carried by said ring for engagement with said cam followers; an hydraulic cylinder for iti'tlllltlllg said ring; a piston within said cylinder; and a system of levers and links connecting said piston with said ring, whereby movement of said piston causes partial. rotation of said ring, to move said mold segments inwardly.

8. A concrete-pipe machine comprising an inner mold; an outer mold capable of con traction and expansion, said outer mold being formed of a plurality of radially morable segments; a cam follower secured to the back of each mold segment; an oscillator-g ring encircling said segments; a plurality of cams carried by said ring for engagement with said cam followers; spring associated with each segment for causing its follower to follow the corresponding cam of said ring; and mechanism for oscillating said ring to cause contraction and expansion of said outer mold.

9. Aconcrete-pipe machine comprising an inner mold capable of contraction to the molded pipe; an outer mold capable of contraction and expansion. said outer mold being formed of a plurality of radially mor able segments; a cam follower secured to the back of each mold segment; an oscillatory ring encircling said semnents: a plu rality of cams carried by said ring for engagement with said cam followers; a s n'in; associated with each segment for causing its follower to follow the correspondinp cam o l i said ring; and mechanism for oscillating said ring to cause contraction and expansion of said outer mold.

10. A concrete-pipe machine comprising an inner mold capable of contraction to free the molded pipe. said inner mold being formed of a plurality of radially movable segments having lugs projecting from their inner surfaces; means for contracting said inner mold comprising a central longitud nally movable rod carryingwedge blocks adapted for engagement with the lugs of said inner mold segments; an outer mold capable of contraction and expansion, said outer mold being formed of a plurality of: radially movable segments; a cam follower secured to the back of each mold segment; an oscillatory ring encircling said segments;

a plurality of cams carried by said ring for engagement with said cam followers; a spring associated with each segment for causing" its follower to follow the corresponding cam of said ring; and mechanism for oscillating said rin to cause contraction and expansion of said outer mold.

11. A. concrete-pipe machine con'iprising a rotatable inner mold capable of contraction and expansion, said inner mold comprising a plurality of radially movable segments l iari ng guide fingers and compression lugs project ing' from their inner surfaces, a rotatable supporting tube having radially soclrctcd members adapted to receive the guide {inger of the mold segments and having a longitudinally directed slot in the region of the compression lugs of said segments, an annular wedge ring slidably mounted on said tube and adapted for engagement with said compression lugs, a longitudinally morable rod within said tube and connected through the slot thereof with said. wedge ring whereby movement oil. said rod can. i the expansion ofsaid mold. and springs sociated with said segments for causing the rontraction of said mold; an outer mold capable of contraction and. expansion; means for contracting said outer mold; and means for rotating said inner mold.

l2. A concrete-pipe machine comprising inner and outer cylindrical molds each formed of a series of separate radially movable parallel segmental bars the molding surface of each bar being made up of a plurality of parallel. longitudinally disposed segments separated by narrow slits leading into enlarged drain passages behind said surface.

13. A concretepipe machine comprising a rotatable inner mold capable of contraction to tree the molded pipe and an outer mold capable of contraction to compress the con crete and of expansion to free the molded pipe. the molding surfaces being formed of a plurality of parallel segments separated by narrm-v slits leading into enlarged drain passages behind said surfaces; means for contracting and expanding said molds; and means for rotating said innermold.

14L. A. concretepipe machine comprising a rotatable inner mold. and an outer mold, each capable of contraction and expansion. and each formed of a series of separate radially movable parallel segmental bars, the molding surface of each bar being made up of a plurality of segments separated by narrow slit leading: into enlarged drain passages behind said surface; means for contracting and expanding said molds; and means for rotating said inner mold.

15. A. concrete-pipe machine comprising vertically disposed inner and outer molds capable of contraction and expansion, respectively to free the molded pipe; separate r Oi) molds.

17. A concrete-pipe machine comprising inner and outer molds capable of adjust ment to free the molded pipe; separate eml molds; means for removing the molded pipe, with said end molds positioned thereupon, from the machine; and means for supporting the freed molded pipe and for lowering the same from said inner and outer molds to said removing means.

18. A concrete-pipe machine comprising vertically disposed inner and outer molds capable of adjustment to free the molded pipe; separate end molds; means for removing the molded pipe with said end molds positioned thereupon, from the machine; de'vices for lowering the freed molded pipe from said inner and outer molds and placing the same upon said removing means; and a hydraulic cylinder for actuating said lowering devices.

19. In a machinefor making reinforced concrete pipe sections, each section having embedded therein a reinforcing coil; inner and outer molds capable of adjustment to free the molded pipe; separate end molds; and means for positioning said end molds and the reinforcing coil between said inner and outer molds.

20. In a machine for making reinforced concrete pipe sections, each section having embedded therein a reinforcing coil; inner and outer molds capable of adjustment to free the molded pipe; separate end molds; and means for positioning said end molds and the reinforcing coil between said inner and outer molds, and. for supporting the freed molded pipe and lowering the same from between said inner and outer molds.

21. In a machine for making reinforced concrete pipe sections each section having embedded therein a reinforcing coil; inner and outer molds capable of adjustment to free the molded pipe; separate end molds; carrier means supporting said end molds and the reinforcing coil and positioning the same below the inner and outer molds, and for removing the molded pipe, with said end molds positioned thereon, from the machine; and elevating means for lifting the end molds and the reinforcing coil from said carrier means and positioning the same between said inner and outer molds, and for lowering the freed molded pipe from between said inner and outer molds on to said carrier means.

22. A- concrete-pipe machine comprising vertically disposed inner and outer molds; separate end molds; a feed hopper for the poured concrete having a feed aperture positioned above the outer mold; and means for temporarily engaging the upper end mold and raising the same above said feed aperture and for forcibly lowering said up per end mold into its final position.

28. A concrete-pipe machine comprising vertically disposed inner and outer molds; separate end molds; a feed hopper for the poured concrete having a feed aperture positionedabove the outer mold; a gate for closing said aperture; means for forcibly closing said gate; and means for temporarily engaging the upper end mold and raising the same above said aperture and for forcibly lowering said upper end mold into its final position.

24. A concrete-pipe machine comprising vertically disposed inner and outer molds; separate end molds; a feed hopper for the poured concrete having a feed aperture positioned above the outer mold; means for posi-- tioning said end molds between said inner and outer molds and for removing the molded pipe, with said end molds positioned thereon, from between said inner and outer molds; and means for raising the upper end mold above said feed aperture during the pouring operation, and for subsequently forcibly lowering said upper end mold into its final position.

25. A concrete-pipe machine comprising a base; vertically disposed supporting columns rising therefrom; associated inner and outer cylindrical molds carried by the upper portion of said columns, said molds being capable of adjustment to free the molded pipe; and means associated with said base for supporting and lowering the freed molded pipe from its molding position between said inner and outer molds.

26. A concrete-pipe machine comprising a base; vertically disposed supporting columns rising therefrom; associated inner and outer pipe molds carried by said columns; and means for raising and lowering both of said molds as a unit upon said columns.

27. A concrete-pipe machine comprising a base; vertically disposed supporting columns rising therefrom; a frame adjustably mounted on said columns; associated inner and outer pipe molds carried by said frame; and means for raising and lowering said frame upon said columns.

28. A concrete-pipe machine comprising a base; vertically disposed threaded supporting columns rising therefrom; a frame slidably mounted on said columns; associated pipe molds carried by said frame; and nuts mounted on said columns, in threaded engagement therewith for supporting and adjusting said frame.

29. A concrete-pipe machine comprising a base; vertically disposed threaded supporting columns rising therefrom; a frame slidably mounted on said columns; associated pipe molds carried by said frame; interconnected nuts mounted on said columns, in threaded engagement therewith, for supporting said frame; and means for simultaneously operating all of said nuts to raise and lower said frame.

30. A concrete-pipe machine comprising a base; vertically disposed threaded supportname to this specification in the presence of 30 two subscribing witnesses.

J ULIUS G. ZWIUKER.

Witnesses:

WILLIAM F. BooTH, J11, D. B. RICHARDS. 

